Flashlights utilizing two or more dry cell batteries as their source of electrical energy are well known in the art. A miniature hand-held flashlight with variable dispersion was developed to improve the functions of flashlights, as shown in prior art FIGS. 5 TO 7.
The prior art flashlight comprises a cylindrical tube 6 containing at least two miniature dry cell batteries disposed in a series arrangement. A lip 69 is formed at the front end of the tube 6. A head 7 is threadably connected to one end of the tube 6. A cap 8 with a parabolic reflector 81 is disposed within the outer end of the head 7. A side conductor 62 and a center conductor 63 are disposed between a first insulator receptacle 61 and a second insulator receptacle 71. The prongs 73 of a light bulb 75 are respectively connected to the side and center conductors 62, 63. The center electrode 67 of the forwardmost battery 66 is urged into contact with the center conductor 63. When the conventional flashlight is in "off" condition, as shown in FIG. 6, the first insulator receptacle 61 is pushed rearward by the second insulator receptacle 71 so that a space is formed between the foremost surface by the first insulator receptacle 61 and the lip 69 on the forward end of the tube 6. Therefore, the side conductor 62 is separated from contact with the lip 69 on the tube 6. Referring next to FIG. 7, appropriate rotation of the head 7 causes the head to move forward a sufficient distance so that the reflector 81 and the insulator receptacles 61, 71 can be pushed forward by the action of the spring 64 until the side conductor 62 comes into contact with the lip 69 of the tube 6. At that point, the side conductor 62 electrically contacts the lip 69 of the tube 6 and turns the flashlight to "on" condition. Further rotation of the head 7 causes a relative motion between the reflector 81 and the light bulb 75 so as to vary the dispersion of the light beam.
There are some problems concerning this prior art:
(a) No stops are provided between the head and the tube 6, therefore, the head and tube are easily separated by further rotation of the head 7.
(b) After rotating the head a sufficient distance, a water sealing ring provided on the tube 6 is exposed, thus the water seal between the head 7 and the tube 6 is ineffective. Furthermore, no sealing ring is provided between the cap 8 and the lens 83.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the flashlight.